1. Field of the Invention
The field of this invention relates to remote-reading water meters, and more particularly relates to the mounting of an antenna/transponder unit within a meter box.
2. Description of the Related Art
A conventional remote-reading water meter has an antenna/transponder unit which is installed in a meter box through the box lid, attached to the lid, or below the lid. Typically the meter box is buried in a pit below ground level. After a quantity of water flows through the meter, water consumption data is transmitted by radio frequency (RF) signals generated by the antenna/transponder. Registers in the meters have an encoder that works on a shaft that rotates as water passes through. The registers generate a signal that is transmitted to the antenna/transponder which advances the human-readable meter dials in a well-known manner and stores the data in the antenna/transponder's electronic memory cache. The remote receiver can be periodically actuated to send out a coded signal that turns on a transmitter in the transponder of a nearby meter. The transponder responds to the coded signal by generating the RF signals that contain the stored data.
The antenna of a conventional remote-reading meter is directional and radiates the RF signals in a relatively narrow beam. The beam is directed at an upward angle from a horizontal plane. The angle is selected to be optimum for transmitting RF signals to any nearby above-ground receiver that can pick up the signals. In certain areas a human meter reader carries a hand-held receiver that picks up the RF signals for recording the data from individual meters. Other areas can use mobile receivers in vehicles that are driven along roads in proximity to the meters for automatic pick up of the signals, and others utilize a fixed base receiving unit that receives the transmissions from the pit.
In typical remote-reading water meters, the meter box contains a hollow tube of plastic material, such as PVC, which is mounted vertically to house the antenna/transponder. Should the meter box become flooded with water, the antenna/transponder can float to the top and exit the tube's upper end. Then after the water recedes, the antenna/transponder can float down with the water outside the pipe and come to rest on its side on the pit floor. This can result in the remote receiver being unable to pick up the RF signals because, with the antenna/transponder on its side, the beam would no longer be transmitted at the optimum angle from the horizontal and thus not reach the receiver. The remote receiving capability of the meter would then be lost, causing a disruption in collecting the data. Other common fixtures include the drilling of holes in the meter box lid, attaching the antenna to the bottom of the lid, or attaching the antenna to a piece of PVC pipe or rebar which is driven into the ground.
In addition, there exist arrangements that incorporate the antenna into the box lid. But this can lead to antenna damage or wire lead damage. Thus, when the lid is removed for servicing and then dragged across a sidewalk or street the antenna can be damaged as a result of its location at the bottom of the lid.